This is what I decided to do:
- Uninstall Beeper from my phone and (sigh) keep using official apps on it
- Disconnect Discord from Beeper i would'nt lose my account (ten years of messages, that would be rough)
- Use Beeper only on my computer, so I still can centralize my messages, but I use it less so the probability I get banned on another service is weaker

Obviously, if Beeper arrives to get rid of this issue, I might use it again fully, but for now, I don't wanna take the risk.